US Bridges

Or 18 (hwy 39) over Muddy Creek

Fair

Yamhill County, Oregon · 8 MI SW of Mcminville · Structure no. 02404A039 03798

Built
1978
47 years old
Condition
Fair
inspected November 2024
Type
Slab
Prestressed Concrete
Length
99 ft
3 main spans
Daily traffic
16,258
2022 count
Owner
State
State Highway Agency

About this bridge

Or 18 (hwy 39) over Muddy Creek is a prestressed concrete slab carrying Or 18 (hwy 39) over Muddy Creek in Yamhill County, Oregon. It was built in 1978, so it is 47 years old, younger than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 16,258 vehicles a day, roughly 9% of them trucks, projected to reach 16,400 by 2042. The structure is 99 ft (30.2 m) long and 44 ft wide. If it were closed, the detour would be 10.6 mi (17 km).

Location

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CarriesOr 18 (hwy 39)
CrossesMuddy Creek
Location8 MI SW of Mcminville
RouteState Highway 18
CountyYamhill County
StateOregon
Coordinates45.12709, -123.30277
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating29.3 US tons
Inventory rating22.5 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20
Structure length99 ft (30.2 m)
Longest span33 ft (10.1 m)
Deck width44 ft (13.4 m)
Roadway width43 ft (13.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,258 (2022)
Projected traffic16,400 by 2042
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed10.6 mi (17 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Or 18 (hwy 39) over Muddy Creek built?

It was built in 1978, making it 47 years old in 2025.

What condition is Or 18 (hwy 39) over Muddy Creek in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in November 2024.

How much traffic does Or 18 (hwy 39) over Muddy Creek carry?

About 16,258 vehicles per day (2022 count), of which roughly 9% are trucks.

How long is Or 18 (hwy 39) over Muddy Creek?

The structure is 99 ft (30.2 m) long with a longest span of 33 ft (10.1 m) and a deck 44 ft wide.

Who owns Or 18 (hwy 39) over Muddy Creek?

It is owned by the State Highway Agency.